Tightening Of Tight Junctions Research Articles

글루타민 결핍에 따른 Tight Junction 및 MMPs 활성 조절을 통한 전립선 암세포의 침윤 억제 현상

암세포를 포함한 생체 내 빠른 분열을 요구하는 세포 집단에서 세포 내 구성요소 및 에너지원으로서 글루타민의 요구량이 증대되지만, 종양세포의 글루타민 의존적 대사작용에 관한 기전은 여전히 잘 알려진 바 없다. 본 연구에서는 LnCaP 전립선 암세포의 이동성 및 침윤성에 미치는 글루타민 결핍효능을 조사하였다. 본 연구의 결과에 의하면 LnCaP 세포에서 글루타민 결핍에 의하여 세포의 이동성 및 세포의 침윤성이 현저하게 억제되었으며, 이러한 이동성 및 침윤성 억제는 TIMPs의 발현 증대에 의한 MMPs의 발현 감소 및 그들의 효소적 활성 저하와 연관성이 있었다. 또한 글루타민이 결핍된 조건에서 배양된 LnCaP 세포에서 TER의 현저한 증가가 관찰되었는데, 이는 TJs의 조절인자인 claudin family 발현의 차단에 의한 것으로 생각되어진다. 본 연구의 결과에 의하면 암세포의 증식에서 글루타민의 결핍은 TJ의 결합력 증대와 MMPs의 활성을 저하시킴으로써 암세포 전이에 가장 기본적인 과정인 암세포의 이동성과 침윤성을 억제시킬 수 있을 것으로 생각된다.

Bufalin prevents the migration and invasion of T24 bladder carcinoma cells through the inactivation of matrix metalloproteinases and modulation of tight junctions

Bufalin, a cardiotonic steroid extracted from toad venom, has generally been known to possess a range of biological activities; however, only a few studies have reported the anti-metastatic activity of bufalin. In the present study, we investigated the inhibitory effects of bufalin on cell migration and invasion, two critical cellular processes that are often deregulated during metastasis, using the human bladder cancer cell line, T24. Within the concentration range that was not cytotoxic, bufalin markedly inhibited the cell motility and invasiveness of T24 cells. The inhibitory effects of bufalin on cell invasiveness were associated with the tightening of tight junctions (TJs), which was demonstrated by an increase in transepithelial electrical resistance (TER). Bufalin treatment also repressed the levels of claudin proteins (claudin-2, -3 and -4) and the major components of TJs that play key roles in the control and selectivity of paracellular transport. Furthermore, the activities of matrix metalloproteinase (MMP)‑2 and -9 in T24 cells were dose‑dependently inhibited by treatment with bufalin and this also correlated with a decrease in their mRNA and protein expression levels; however, the mRNA and protein levels of the tissue inhibitor of metalloproteinase (TIMP)‑1 and -2 were increased. In addition, these effects were related to the increased phosphorylation of the extracellular signal-regulated protein kinase (ERK) pathway. The inhibition of ERK (PD98059) significantly prevented the bufalin‑induced suppression of T24 cell migration. These findings suggest that bufalin inhibits the migration and invasion of T24 cells by modulating the activity of TJs and MMPs, possibly in association with the activation of ERK.

Anti-invasive effects of decitabine, a DNA methyltransferase inhibitor, through tightening of tight junctions and inhibition of matrix metalloproteinase activities in AGS human gastric carcinoma cells

The DNA methyltransferase inhibitor decitabine, 5-Aza-2'-deoxycytidine, possesses anti-metabolic and anticancer activities in various cancer cells. However, the biochemical mechanisms underlying decitabine-induced inhibition of invasiveness and metastasis have not been thoroughly studied. In this study, we investigated the effect of decitabine on the correlation between tightening of tight junctions (TJs) and anti-invasive activity in AGS human gastric cancer cells. Our data indicated that the inhibitory effects of decitabine on cell motility and invasiveness were associated with increased tightness of the TJ, which was demonstrated by an increase in transepithelial electrical resistance (TER). Immunoblotting results indicated that decitabine repressed the levels of the claudin proteins, major components of TJs that play a key role in the control and selectivity of paracellular transport. Furthermore, matrix metalloproteinase (MMP)-2 and -9 activity in the AGS cells was dose-dependently inhibited by treatment with decitabine, and this was correlated with a decrease in mRNA and protein expression. In addition, these effects were related to inactivation of the phosphoinositide 3-kinase (PI3K)/Akt pathway in AGS cells. In conclusion, this study suggests that TJs and MMPs are critical targets of decitabine-induced inhibition of invasiveness in AGS human gastric cancer cells.

Inhibition of migration and invasion of LNCaP human prostate carcinoma cells by cordycepin through inactivation of Akt

Cordycepin (3'-deoxyadenosine), a major bioactive compound of Cordyceps militaris, has many pharmacological actions, such as anti-inflammatory and anticancer activities. In this study, the relationship between inhibition of cell motility and anti-invasive activity by cordycepin in LNCaP human prostate carcinoma cells was investigated. Within the concentration range that was not cytotoxic, cordycepin time-dependently inhibited cell motility and invasiveness of LNCaP cells. The inhibitory effects of cordycepin on cell invasiveness were associated with tightening of tight junctions (TJs), which was demonstrated by an increase in transepithelial electrical resistance (TER). Immunoblotting indicated that cordycepin decreases levels of claudin proteins, which are major components of TJs that play a key role in control and selectivity of paracellular transport. Furthermore, cordycepin inhibited the expression and activity of matrix metalloproteinase (MMP)-2 and MMP-9, and simultaneously increased levels of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2. These effects were related to inactivation of the phosphoinositide 3-kinase (PI3K)/Akt pathway in LNCaP cells. These findings suggest that cordycepin inhibits the migration and invasion of LNCaP cells by downregulating the activity of TJs and MMPs, possibly in association with suppression of Akt activation.

Anti-invasive Activity of Ethanol Extracts of Ganoderma lucidum through Tightening of Tight Junctions and Inhibition of Matrix Metalloproteinase Activities in Human Gastric Carcinoma Cells

This study investigated the effect of ethanol extracts of Ganoderma lucidum (EGL) on the correlation between tightening of the tight junctions (TJs) and the anti-invasive activity in human gastric adenocarcinoma AGS cells to elucidate further the possible anticancer mechanisms that G lucidum exerts. Within the concentrations of EGL that were not cytotoxic, EGL markedly inhibited the cell motility and invasiveness in a concentration-dependent manner. The activities of matrix metalloproteinases (MMP)-2 and MMP-9 in AGS cells were dose-dependently inhibited by treatment with EGL, and this was correlated with a decrease in expression of their mRNA and proteins and the upregulation of the expression of the tissue inhibitors of metalloproteinases. The anti-invasive activity of EGL was also found to be associated with the increased tightness of the TJ, which was demonstrated by an increase in transepithelial electrical resistance. Additionally, EGL repressed the levels of the claudin family members, which are major components of TJs that play a key role in the control and selectivity of paracellular transport. Furthermore, the levels of E-cadherin, a type I transmembrane glycoprotein, were inhibited by EGL treatment, however, those of snail, an epithelial to mesenchymal transition regulator and zinc finger transcription factor, were concentration-dependently increased in response to EGL treatment. Although further studies are needed, the present study indicates that TJs and MMPs are crucial targets of EGL-induced anti-invasiveness in human gastric cancer AGS cells.

Inhibition of Matrix Metalloproteinase Activities and Tightening of Tight Junctions by Diallyl Disulfide in AGS Human Gastric Carcinoma Cells

The effect of diallyl disulfide (DADS), a major component of an oil-soluble allyl sulfide garlic (Allium sativum) derivative, on the correlation between anti-invasive activity and tightening of tight junctions (TJs) was investigated in human gastric adenocarcinoma AGS cells. Our data indicated that the inhibitory effects of DADS on cell motility and invasiveness were found to be associated with increased tightness of the TJs, which was demonstrated by an increase in transepithelial electrical resistance. Activities of matrix metalloprotease (MMP)-2 and -9 in AGS cells were dose-dependently inhibited by treatment with DADS, and this was also correlated with a decrease in expression of their mRNA and proteins; however, tissue inhibitor of metalloproteinase (TIMP)-1 and -2 mRNA levels and proteins were increased. Additionally, immunoblotting results indicated that DADS repressed the levels of claudin proteins (claudin-2, -3, and -4), major components of TJs that play key roles in control and selectivity of paracellular transport. Although further studies are needed, these results suggest that DADS treatment may inhibit tumor cell motility and invasion and, therefore, act as a dietary source to decrease the risk of cancer metastasis.

AGS 인체 위암세포에서 톳 에탄올 추출물에 의한 침윤성 저해

In this study, we investigated the effects of ethyl alcohol extracts of Hizikia fusiforme (EHF) on the correlation between tightening of tight junctions (TJs) and anti-invasive activity in human gastric adenocarcinoma AGS cells. Inhibitory effects of EHF on cell proliferation, motility, and invasiveness were found to be associated with increased tightness of the TJs, which was demonstrated by an increase in transepithelial electrical resistance. Activities of matrix metalloprotease (MMP)-2 and -9 in AGS cells were dose-dependently inhibited by treatment with EHF, and this was also correlated with a decrease in expression of their mRNA and proteins; however, tissue inhibitor of metalloproteinase (TIMP)-1 and -2 mRNA levels were increased. Additionally, immunoblotting results indicated that EHF repressed the levels of claudin proteins (claudin-1, -3, and -4), major components of TJs that play key roles in control and selectivity of paracellular transport. Furthermore, EHF decreased expression of insulin such as growth factor-1 receptor proteins, while concurrently increasing that of thrombospondin- 1 and E-cadherin. In conclusion, these results suggest that EHF treatment may inhibit tumor cell motility and invasion, and therefore act as a dietary source to decrease the risk of cancer metastasis.

Anti-invasive activity of diallyl disulfide through tightening of tight junctions and inhibition of matrix metalloproteinase activities in LNCaP prostate cancer cells

Diallyl disulfide (DADS) is a major component of an oil-soluble allyl sulfide garlic ( Allium sativum) derivative, which has been shown to exert a potential for anti-cancer activity. However, the biochemical mechanisms underlying DADS-induced anti-invasiveness and anti-metastasis have not been thoroughly studied. In this study, we investigated the effect of DADS on the correlation between tightening of tight junctions (TJs) and anti-invasive activity in human prostate carcinoma LNCaP cells. Inhibitory effects of DADS on cell motility and invasiveness were found to be associated with increased tightness of the TJ, which was demonstrated by an increase in transepithelial electrical resistance (TER). Additionally, immunoblotting results indicated that DADS repressed the levels of the claudin proteins, which are major components of TJs that play a key role in control and selectivity of paracellular transport. Furthermore, the activities of matrix metalloproteinase (MMP)-2 and -9 in LNCaP cells were dose-dependently inhibited by treatment with DADS, and this was also correlated with a decrease in expression of their mRNA and proteins. Although further studies are needed, the present study indicates that TJs and MMPs are critical targets of DADS-induced anti-invasiveness in human prostate cancer LNCaP cells.

흑마늘 추출물이 인체위암세포의 tight junction 투과성 조절과 세포 침윤성 억제에 미치는 영향

Garlic (Allium sativum) has been well-known as a folk remedy for a variety of ailments since ancient times, and it is well documented that enhanced garlic consumption leads to a decrease in incidences of cancer. Tight junctions (TJs) are critical structures for the maintenance of cellular polarity, acting as paracellular permeability barriers and playing an essential role in regulating the diffusion of fluid, electrolytes and macromolecules through the paracellular pathway. Matrix metalloproteinases (MMPs) have been implicated as possible mediators of invasiveness and metastasis in some cancers. In this study, we investigated the potential effects of water extract of aged black garlic (ABG) on the correla-tion between tightening of TJs and anti-invasive activity in human gastric carcinoma AGS cells. The inhibitory effects of ABG on cell motility and invasiveness were found to be associated with increased tightness of TJs, which was demonstrated by an increase in transepithelial electrical resistance. Additionally, the activities of MMP-2 and -9 in AGS cells were inhibited by treatment with ABG, and this was also correlated with a decrease in the expression of their mRNA and proteins. Furthermore, RT-PCR and immunoblotting results indicated that ABG repressed the levels of the claudin proteins, major components of TJs that play a key role in the control and selectivity of paracellular transport. In conclusion, these results suggest that ABG treatment may inhibit tumor metastasis and invasion, and therefore may act as a dietary source to decrease the risk of developing cancer. Keywords : Aged black garlic, tight junction, MMP, invasion

The ethyl alcohol extract of Hizikia fusiforme inhibits matrix metalloproteinase activity and regulates tight junction related protein expression in Hep3B human hepatocarcinoma cells.

We tested the correlation between the tightness of tight junctions (TJs) and the anti-invasive activity of the ethyl alcohol extract of Hizikia fusiforme (EHF) in Hep3B human hepatocarcinoma cells. EHF inhibited cell proliferation, motility, and invasiveness, which were associated with increased TJ tightness, as demonstrated by an increase in transepithelial electrical resistance. EHF dose-dependently decreased the secretion of matrix metalloprotease-2 and -9, which correlated with a decrease in mRNA and protein expression, but increased tissue inhibitor of metalloproteinase-1 and -2 mRNA levels. Additionally, immunoblotting results indicated that EHF suppressed the major components of TJ, claudins (-1, -3, and -4), which play a key role in the control and selectivity of paracellular transport. These data indicate that EHF may inhibit cancer cell invasion through the tightening of TJs, which may counteract the up-regulation of claudins. Furthermore, EHF treatment decreased the expression of insulin-like growth factor-1 receptor proteins, while concurrently increasing that of thrombospondin-1 and E-cadherin. In conclusion, these results suggest that EHF treatment may inhibit tumor metastasis and invasion and therefore act as a dietary resource for decreasing the risk of developing cancer.

인체유방암세포의 tight junction 기능 조절을 통한 genistein의 암세포 침윤 억제 효과

Tight junctions (TJs) that act as paracellular permeability barriers play an essential role in regulating the diffusion of fluid, electrolytes and macromolecules through the paracellular pathway. In this study, we investigated the correlation between the tightening of TJs, permeability and the invasive activity of genistein - a bioactive isoflavone of soybeans - in human breast carcinoma MCF-7 and MDA-MB-231 cells. The inhibitory effects of genistein on cell proliferation, motility and invasiveness were found to be associated with the increased tightness of the TJs, which was demonstrated by an increase in transepithelial electrical resistance and a decrease in paracellular permeability. Additionally, the immunoblotting results indicated that genistein repressed the levels of the proteins that comprise the major components of TJ, claudin-3 and claudin-4, which play a key role in the control and selectivity of paracellular transport. Furthermore, genistein decreased the metastasis-related gene expressions of insulin like growth factor-1 receptor and snail, while concurrently increasing that of thrombospondin-1 and E-cadherin. In addition, we demonstrated that claudins play an important role in the anti-motility and invasiveness of genistein using claudin-3 small interfering RNA. Taken together, our results indicate a possible role for genistein as an inhibitor of cancer cell invasion through the tightening of TJs, which may counteract the up-regulation of claudins. In addition, our results indicate that this may be beneficial for the inhibition of tumor metastasis.

Anti-invasive activity of sanguinarine through modulation of tight junctions and matrix metalloproteinase activities in MDA-MB-231 human breast carcinoma cells

Tight junctions (TJs) are critical structures for the maintenance of cellular polarity, acting as paracellular permeability barriers and playing an essential role in regulation of the diffusion of fluid, electrolytes and macromolecules through the paracellular pathway. Matrix metalloproteinases (MMPs) have been implicated as possible mediators of invasiveness and metastasis in some cancers. In this study, it was investigated the effect of sanguinarine, a benzophenanthridine alkaloid, on the correlation between the tightening of TJs and the anti-invasive activity in human breast carcinoma MDA-MB-231 cells. The inhibitory effects of sanguinarine on cell proliferation, motility and invasiveness were found to be associated with the increased tightness of the TJ, which was demonstrated by an increase in transepithelial electrical resistance (TER). Additionally, immunoblotting results indicated that sanguinarine repressed the levels of the claudin proteins, major components of TJs that play a key role in the control and selectivity of paracellular transport. Furthermore, the activities of MMP-2 and -9 in MDA-MB-231 cells were dose-dependently inhibited by treatment with sanguinarine, and this was also correlated with a decrease in the expression of their mRNA and proteins.